Milling Equipment

The milling tandem consists of the following:

Mill No. 1 is a 7' three-roll mill installed in 1995. It is equipped with a Donnelly chute and driven by a 2,500-hp. multi-stage turbine through Horsburgh & Scott gear boxes. The high-speed gearbox ratio is 18.215, while the ratio of the low-speed gearbox is 34.533. This mill also is equipped with a force-feed roll driven by an offside crown wheel. Mill roll diameters are 46".

Mill Nos. 2 and 3 are 6.5' mills with force-feed rolls. Roll diameters on these two mills are 40".

Mill No. 4 is a 7' mill operated by a Hagglunds hydraulic drive. The drive consists of two MB1150 hydraulic motors driving the top roll, one MB1150 driving the front roll, and one MB566 hydrualic motor driving the back roll.The hydraulic motors are driven by four independent hydraulic pumps. Power to drive the pumps is derived from a 1,200-hp. Elliott turbine operating at 3,600 rpm. The turbine drives a special David Brown gearbox with four output shafts, to which the motors are connected. This mill's roll diameters are 44". Its force-feed mill roll is driven by a chain.

Mill No. 5 is a 7' mill with a force-feed roll and roll diameters of 44". The mill is driven by a 1,400-hp., 4,400 rpm Elliott turbine through Horsburgh & Scott gearboxes with ratios similar to those in No. 1 mill. Mill No. 5 also is equipped with a force-feed roll driven by an offside crown wheel.

Mill No. 6 was replaced with a Skoda mill having 7' x 48"-diameter rolls. The drive for this mill is driven by a 2,500-hp. multi-stage similar to the No. 5 mill, and the mill also is equipped with a force-feed roll driven by an offside crown wheel.

All six mills are equipped with Donnelly chutes. Mill speeds are controlled by probes installed in the sides of each Donnelly, and all mills are fed by rubber-belt conveyors set at a 60 degree angle.